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Scottsman Ice Machine

I just got home from working on a Scottsman Ice Machine Model # CME 1356RS-32D When I arrive all 5 evap panels were frozen solid with ice build up panel to panel. After putting the unit into harvest a dozen times and pouring hot water to thaw the ice I was able to put the unit into a freee mode. Once it went through a cycle the cubes it harvested were normal good size cubes.

I checked the pressures they seemed alright, maybe a little ow but nothing that the tx and hot gas can't over come. The water float was replaced about six months ago, all other components seem to be functioning.

Another tech was there Sunday afternoon for the same problem he cleaned the unit and left. Not to sure what i should start with. I am starting to wonder if it is an intermittant issue with the board not opening the hot gas bypass.

Probably not harvesting correctly due to cold cold water.
I've had quite a few of these machines not always harvest correctly because the ground water is too cold. If I remember right you can push a couple buttons on the board and reconfigure how soon the water comes on in harvest.

Basically the water shuts off as soon as the unit goes into harvest and the hot gas valve opens. But after a minute or so the inlet water valve opens and starts bringing fresh water in for the next batch. If this happens too soon and the water is too cold it cools the plate off taking away all of the heat for harvest. I realize you didn't see this yet but I bet after a couple batches it will happen. Once one batch doesn't harvest correctly the ice will build up really fast.....

replay

Had a similar problem on another brand. Found the ice sheets forming from ice not completley falling off the sheet, defrost was running too long, and poor cube formation.
I cleaned the float assy, checkede the fill tubes for blockages, found my particular machine used water through the back of the sheet plus hot gas to help drop the cubes.
I cleaned the unit with a wash cycle and ice machine cleaner with citric acid (whatever wasn't nickel safe type). I think the water ports were all fouled from 12 years of running and no cleaning. Steralized it with a couple caps of bleach and another was cylce, cleaned the condenser coil (heavy lint), hasn't had a problem since.
I think defrost cycles are affected by poor heat exchange surface and poor water distribution. If some of the ports are clogged, some cubes become larger than others and get stuck when they try to fall out.

Have you called Scotsman? What did they say? A couple of things to consider are cube shape and temperature. If the cubes are not uniform there will be a 'mass' buidup that used enough water to put it into harvest but is too big to get defrosted off. Second is the harvest time is reset based on something like OA temp or water temp, I can't remember. So if youve got a bad sensor it may be making the harvest too short.. Take your freeze time and harvest times.

Clean the machine. Make sure that ice is forming on every plate front and back. Water inlet solenoid it's a were you want to look next. They can be very intermittent. If that doesn't work I have 5 other suggestions on why is icing up. Good luck

So a week later heres what has happened. I cleaned, cleaned, cleaned, and cleaned it again. Put it back together and strted to pray it would work properly. It harvested good ice and cubes. Called the next day and a full bin, called everyday and not one problem. Called again today after a friday night and still working.

So I guess the apprentice who cleaned it before me missed something or didn't clean it properly.

We have maintenance contract with this Pub for all equipment and have it scheduled to clean it once a year. How often do you reccommend cleaning an ice machine. We are there quarterly for a full HVAC inspection.

Minimum 2 times a year. But 4 would be better. When cleaning that Scotsman make sure you remove the water distribution tubes on top the evaps. Look inside them I've seen all kinds of things plugging them up.